Ice resurfacing blade

ABSTRACT

The blade is made of heat-treated stainless steel that has one or two sharp edges for resurfacing ice, such as at an ice rink with an ice resurfacing machine. The preferred material is stainless steel. The blade lasts four times longer than a conventional blade, reducing the sharpening interval and reducing the cost of removal, replacement, shipping, and re-sharpening. Reduced maintenance lowers the chance that a worker will be injured during maintenance activities. The life of the blade is about 15 years compared to one year for conventional bladed. It does not corrode during storage. Because the blade is sharper and stronger than conventional ice resurfacing blades, it provides a flatter and smoother finished ice surface than conventionally available. The improved blade allows the ice to be resurfaced more quickly by allowing deeper cuts and faster operation of the resurfacing machine itself.

CROSS REFERENCE TO RELATED APPLICATION

[0001] This application claims the benefit of U.S. Provisional Application No. 60/329,940, filed Oct. 17, 2001. Applicant requests that the Disclosure Document Number 495874, filed at the United States Patent and Trademark Office on Jun. 18, 2001 be associated with this application.

FIELD OF THE INVENTION

[0002] This invention relates to a device for cutting and smoothing ice with an ice resurfacing machine.

BACKGROUND OF THE INVENTION

[0003] Since the introduction of the first ice resurfacing machine in the 1940s by Frank Zamboni, the technology has changed little. He experimented with machines that would shave, scrape, wash and squeegee the skating rink ice surface before putting down a fresh layer of water. Today, perhaps the best known of these are the Zamboni® and the Olympia ice resurfacing machines. Zamboni® is a registered trademark of Frank J. Zamboni & Co., Inc. Olympia is the registered trademark of Leclair Equipment Ltd. The machines employ a large metal blade which scrapes the surface of the ice a precise amount in order to provide an ice surface which is free of defects and which can be left smooth by the introduction of a thin layer of water, which promptly freezes into a new, smooth ice surface.

[0004] An ice rink eventually becomes rough and pitted plus dust and dirt particles dull it. The ability to quickly and effectively resurface the ice is important to skating and to the development of artificial ice rinks. Before ice resurfacing machines, ice surfaces were maintained manually, using scrapers, towels, a water hose and squeegees. Resurfacing a regulation size rink was time-consuming and labor intensive.

[0005] Early ice resurfacing machines cost about $5,000 and were hand built on war-surplus jeeps. Today, ice resurfacing machines can cost about $60,000 and are mass-produced. Every ice rink has at least one. Professional hockey teams typically use two machines to cut down on the time needed to resurface the ice between periods. Most ice resurfacing machines have a maximum speed of 9 to 10 mph and weigh as much as 6,000 pounds.

[0006] In hockey, the ice is resurfaced before the game, after warm-ups, between periods, and when the game is over. With two resurfacing machines, it takes three minutes to complete the floor, each making four full passes up the ice. With one, it takes between six and seven minutes with eight full passes up the length of the ice.

[0007] The blade scrapes a {fraction (1/16)}-inch to ⅛-inch layer of ice off the ice surface. The blade is as wide as the machine and looks like a very large razor blade. The amount of ice taken off depends on the ice conditions. The more use the ice has, the rougher the surface becomes and the deeper the blade must cut.

[0008] While Olympia® ice resurfacing machines have an 84-inch long, ½-inch thick blade, most Zamboni® ice resurfacing machines have a 77-inch long, ½-inch thick blade. The metal blades are typically about 6-inches wide. The blades are attached to the ice resurfacing machine by means of numerous removable bolts, typically ten or more.

[0009] The blades must frequently be sharpened, which requires removal from their securely mounted position under the resurfacing machine. The old blade is usually replaced immediately with a newly sharpened blade. The procedure is labor intensive and therefore costly to the owner of the resurfacing machine. Ice rinks lose business if the quality of the ice surface is not maintained in a smooth state, thus requiring frequent use of the resurfacing machine.

[0010] The replacement procedure is also dangerous. Each blade weighs about 50 pounds and has one very sharp edge. The blade can easily sever an appendage, such as a finger, foot or hand, if it falls. The blade is at its most dangerous during replacement when the worker must reach under the machine and install ten or more bolts to secure the blade in place. Further, the used blades and new replacement blades must be kept stored at the ice rink.

[0011] Used blades are usually re-sharpened. Because of the size of the blade and the requirement that the blade be very straight and very sharp, sharpening must be done by a machine shop on expensive equipment. This requires that the blades be shipped to the machine shop and returned to the ice rink after sharpening.

[0012] The blades have a limited life before they are scrapped because each sharpening procedure removes metal from the edge of the blade, thereby reducing its width.

[0013] The blades also corrode from exposure to the perpetually wet environment of an ice rink. The resulting rust shortens the life of the blade and creates an undesirable staining of both the blade and anything that it comes in contact with, such as the ice rink floor or the technician that replaces the worn blade with a new blade. The machinist must clean the excess rust from the blade before it can be sharpened.

[0014] The blades must be carefully adjusted during use to avoid making too deep of a resurfacing cut. A cut as deep as ⅜-inch will destroy the blade, perhaps requiring it to be scrapped, if not just removed and re-sharpened. Further, the blades are easily damaged if they strike a hard object, such as a metal threshold surrounding the ice rink entry.

[0015] If the blade is not damaged, thereby shortening its useful life, then its normal life is typically about 15 months, after which it must be scrapped. It is normal that a blade will be removed from the resurfacing machine and sharpened twice per week.

[0016] These problems are well known in the resurfacing industry and numerous attempts to find better blades have been attempted. Efforts to use stainless steel failed when it was found that the blades did not hold a sharp edge for as long as conventional 1018 steel blades. Further, efforts to heat treat stainless steels resulted in severe dimensional changes that rendered the blades useless, since they could not be attached to the resurfacing machines, which require that the mounting holes be within about 0.030-inches of center. The cost of the material and the extra processing combined with low blade yields from the machining and heat-treating processes led to a more expensive blade with little or no increased life.

SUMMARY OF THE INVENTION

[0017] The invention is a blade made of stainless steel that has one or two sharp edges for ice reconditioning. The blade can be re-sharpened when it has become dull. The blade may be made of 440C stainless steel and has pre-drilled holes that are threaded to facilitate mounting on the ice resurfacing machine, such as a Zamboni® machine and to avoid having to reach under the machine to install each bolt individually. The mounting hole pattern is designed to allow mounting of the blade to a wide variety of known ice resurfacing equipment. The blade is heat-treated to provide a very hard edge that lasts longer and that cuts deeper than known blades while providing a high quality finished ice surface.

[0018] Because the blade stays sharp longer than a conventional blade, it cuts the ice deeper while leaving the resurfaced ice surface flatter and smoother than is possible with a known blade. The blade is stronger and does not chatter when making cuts as deep as ⅜-inch, a cut that destroys known blades.

[0019] The blade may have two sharp edges, which reduces the cost of blade inventory and reduces the number of blades required for a given resurfacing machine, thus insuring that a blade is available when needed.

[0020] The cost of maintaining the blade is reduced because it has a long life, as long as 15 years. The cost of replacement is reduced because the blade maintains a sharp edge longer, thus requiring removal and re-sharpening at long intervals, on the order of three weeks. Typically, the blade lasts about four times longer than any known blade. Also, stainless steel does not rust when exposed for long durations to the ice resurfacing machine environment at an ice rink.

OBJECTS OF THE INVENTION

[0021] It is an object of the invention to provide a blade with long life for ice resurfacing on an ice rink using an ice conditioning machine.

[0022] It is an object of the invention to provide a metal blade for ice reconditioning that is comprised of stainless steel.

[0023] It is an object of the invention to provide a blade for ice reconditioning that has two sharp edges.

[0024] It is an object of the invention to provide a blade for ice reconditioning that does not corrode during storage or during use.

[0025] It is an object of the invention to provide a metal blade for ice reconditioning that can be re-sharpened.

[0026] It is an object of the invention to provide a metal blade that is mountable to known ice resurfacing devices.

[0027] It is an object of the invention to provide a blade that has reduced vibration during use.

[0028] It is an object of the invention to provide a blade that has replaceable blade elements.

[0029] It is an object of the invention to provide a blade that has pre-mounted threaded studs to facilitate mounting is an ice reconditioning machine.

[0030] Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWINGS

[0031]FIG. 1 illustrates a perspective view of the blade and safety cover.

[0032]FIG. 2 depicts a perspective view of the back of the blade.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0033] An ice resurfacing blade 10 illustrated in FIG. 1 is configured to be mounted to a conventional ice-resurfacing machine. In a preferred embodiment, the ice resurfacing blade 10 is comprised of a corrosion resistant, heat-treatable metal that is as about 77 to 84-inches long. The preferred material is stainless steel such as 440C. Alternative steels include 17-4 ph stainless, 15-5 ph stainless, 13-8 ph stainless, 410 stainless, and 420 stainless. These materials are less advantageous since they are not heat treatable to the same extent as the preferred 440C stainless.

[0034] Alternative embodiments include blades 10 that are comprised of other corrosion resistant materials, such as ceramics, including, alumina, transformation toughened alumina, transformation toughened zirconia, carbides, nitrides, or refractory materials, such as tungsten carbide, tungsten nitride, nitrided steel, and refractory metals, including tungsten, molybdenum, and niobium. The blade 10 may be a composite blade that includes inserts of these materials in a mounting plate, where the corrosion resistant material forms a part of the sharp first use edge 12 or second use edge 14 that retain their sharpness after prolonged use.

[0035] A further alternative embodiment utilizes coatings of hard, corrosion resistant materials, such as ceramic or refractory metals, on the blade 10 so as to enable the blade edge 12 and edge 14 to maintain a sharp edge for prolonged use. Examples of ceramic coatings include diamond, diamond like carbon, and ultra-nanocrystalline diamond.

[0036] It is desired that the blade 10 not be so hard that it may fail in a brittle manner during use. It is also desirable that the blade 10 be capable of being machined to sharpen the edge of first use 12 and, if a double edge blade, the edge of second use 14. An alternative embodiment has the edges 12 and 14 on different faces, for example, first use edge 12 is on front surface of blade 30 and second use edge 14 is on back surface of blade 42. This is not preferred for safety reasons, since in the preferred design both edges 12 and 14 are protected with one safety cover 20.

[0037] In a preferred embodiment, the blade 10 is machined to the approximate final dimensions, including placing the sharp edges 10 and 12 at a known blade angle 16 that is preferably approximately 30°. In alternative embodiments, the blade angle 16 may vary between about 15° and 65°.

[0038] It is also preferred to machine receiver holes 32 each containing a receiver hole step 34 before heat treatment. In a preferred embodiment there are approximately 10 holes that are placed along the long axis of blade 10 and approximately in the middle of the width of blade 10 so as to align with the required configuration of the ice resurfacing machine. Each hole 32 is identical to the other.

[0039] A bushing 18 is placed in each receiver hole 32 after heat-treatment and machining of the blade 10. Preferably, conventional grinding operations are performed to result in a straight blade 10 and parallel edges 12 and 14. A preferred material for the bushing 18 is 303 stainless steel. The bushing 18 contains a bushing reduction 24 that when pressed into receiver hole 32 bottoms out on receiver hole step 34, thereby securely fixing the bushing 18 in the holes 32. The bushings 18 are machined flat to the front surface 30 and to the back surface 42 of blade 10. Then a series of holes 22 are placed at precise locations so as to align with the required mounting holes in the resurfacing machine. The holes 22 may be through holes with no threading, but in a preferred embodiment each hole 22 is threaded to receive a mounting bolt 40. In this preferred manner the mounting bolt 40 emerges from the back surface 42 as a threaded stud, as shown in FIG. 2. Rather than each bolt 40 having to be placed and mounted individually with a separate nut, while the blade dangles under the resurfacing machine, each mounting bolt 40 is ready to receive a nut after the blade is initially placed in position. In an alternative embodiment, mounting bolt 40 is not threaded, but is attached to a resurfacing machine by means such as pins placed though holes in the bolts 40 that emerge from blade 10.

[0040] The back surface 42 of blade 10 is illustrated in FIG. 2 with the threaded mounting bolts 40, which are securely fastened to the blade 10 by means of the threaded bushing 18, emerging from bushing 18. The bushing reduction 24 having been machined to be flat with back surface 42 of blade 10.

[0041] After the blade 10 has been heat-treated the final machining is performed to place straight sharp edge of first use 12 and straight edge of second use 14 parallel to the longitudinal axis of the blade 10 and parallel to each other. The heat treatment is preferably accomplished to result in an extremely hard material having a preferred hardness of about 55 to 60 Rockwell C when the blade 10 material is 440C stainless.

[0042] To achieve extra rigidity in blade 10, an alternative embodiment, not illustrated, is to honeycomb the front surface 32 and/or the back surface 42 of the blade 10. This stiffens the blade without increasing the weight. The resulting blade stiffness leads to reduced vibration helps to insure that the machined ice surface is smooth and ripple free.

[0043] A safety cover 20, illustrated in FIG. 1, is a preferred embodiment wherein the safety cover 20 has dimensions that are approximately equal to the length and width of front surface 30. The safety cover 20 is preferably made of a lightweight material, such as aluminum, but may be comprised of any strong material, such as wood or metal. The safety cover 20 is held in place during shipping, storage, handling, and placement by safety cover bolts 44, preferably one at each end of safety cover 20. The safety cover through holes 46 are not threaded and are aligned with the threaded holes 36 in the front surface 32. Safety cover bolts 44 are securedly attached into safety cover mounting holes 36. It is preferred that the safety cover 20 remains in place on blade 20 until blade 20 is mounted and secured to the resurfacing machine.

[0044] Obviously, many modifications and variations of the present invention are possible in light of the above teachings. It is therefore to be understood that, within the scope of the appended claims, the invention may be practiced otherwise than as specifically described. 

What is claimed is:
 1. A blade for resurfacing ice that is mounted to a resurfacing machine comprising: a corrosion resistant material; and means for mounting said blade to said machine.
 2. The blade according to claim 1 wherein said means for mounting is at least one mounting bolt that is securedly attached to said blade.
 3. The blade according to claim 1 wherein said blade comprises 440C stainless steel.
 4. The blade according to claim 1 wherein said blade is comprised at least in part of a refractory material.
 5. The blade according to claim 1 wherein said corrosion resistant material is heat treatable to a hardness of about 55 on the Rockwell C scale.
 6. The blade according to claim 1 wherein said blade is comprised of stiffening ridges.
 7. The blade according to claim 1 wherein said blade is comprised of a first use edge and a second use edge.
 8. The blade according to claim 7 wherein said blade has a front surface and said first use edge and said second use edge are located on said front surface.
 9. The blade according to claim 1 wherein said blade is comprised of a safety cover that is removably mounted to said blade.
 10. The blade according to claim 9 wherein said safety cover is removably mounted with at least one screw.
 11. A blade for resurfacing ice that is mounted to a resurfacing machine comprising: a corrosion resistant material; at least one mounting bolt that is securedly attached to said blade; and a first use edge and a second use edge.
 12. The blade according to claim 11 wherein said blade is further comprised of a safety cover that is removably mounted to said blade.
 13. The blade according to claim 11 wherein said blade is comprised of 440C stainless steel.
 14. The blade according to claim 11 wherein said blade has a front surface and said first use edge and said second use edge are located on said front surface.
 15. A method of producing a blade for resurfacing ice comprising the steps of: selecting a corrosion resistant metal; forming said metal to have at least one sharp edge; forming said metal to define at least one receiver hole for receiving a mounting bolt; heat treating said metal to a hardness of about 55 on the Rockwell C scale; machining said blade after said heat treating; and securing a mounting bolt through said blade to align with a defined mounting location.
 16. The method of claim 15 further comprising placing a bushing into said receiver hole for securedly fastening said mounting bolt to said blade.
 17. The method of claim 16 wherein said step of forming said metal forms two sharp edges on said blade.
 18. The method of claim 16 wherein said step of placing a bushing is machining a threaded hole through said bushing.
 19. The method of claim 15 wherein said step of selecting a corrosion resistant metal further comprises selecting a 440C stainless steel.
 20. The method of claim 15 further comprising mounting a safety cover to said blade. 